In recent years, the greenhouse effect caused by carbon dioxide has been pointed out as one cause for global warming phenomena, and there is a tendency that the demand of restraining the emission of carbon dioxide becomes more intense to protect the global environment. For a power generating facility such as a thermal power plant using a large amount of fossil fuel, there has been proposed a method in which carbon dioxide in combustion flue gas is removed and recovered by bringing the combustion flue gas of a boiler into contact with an amine-based carbon dioxide absorbing solution (Patent Document 1).
As a method for removing and recovering carbon dioxide from the combustion flue gas by using a carbon dioxide-absorbing solution, there has been employed a carbon dioxide recovery system in which the combustion flue gas is brought into contact with a carbon dioxide-absorbing solution in an absorption tower, and the absorbing solution having absorbed carbon dioxide is heated in a regeneration tower to liberate the carbon dioxide and to regenerate the absorbing solution, which is circulated again to the absorption tower for reuse. According to the carbon dioxide recovery system, carbon dioxide existing in a gas is absorbed by the absorbing solution in the absorption tower, subsequently the carbon dioxide is separated from the absorbing solution by heating the absorbing solution in the regeneration tower, the separated carbon dioxide is recovered separately, and the regenerated absorbing solution is circulatingly used again in the absorption tower. A reboiler is used to separate and recover the carbon dioxide by heating the absorbing solution in the regeneration tower.
Also, the reboiler is used for heat exchange between a liquid refrigerant and cold water, and as a result, the refrigerant is vaporized, while the cooled cold water is circulated in a building for air cooling (Patent Document 2).